How to quickly decrease solve time?

[retep]

Well everyone is saying prepared solve, so I will offer something else in case that is not what you want to do. Honestly, at your time to improve quickly just do a lot of solves, I found that when I was at your time if I just sat down for like 2 hours and solved my time would drop like 10 seconds by the end, however this often does develop bad habits easier and is probably not as good in the long run as focusing on improving/changing things each practice session. Often some of the things that will make large differences and make you much faster like a week later make you much slower now (ie. switching from beginner method to fridrich, the f2l step will probably slow you down and make your times worse initially but you will get far better in the long run).

Anyway, ya I recommend (if you aren't doing a prepared solve) to just sit down and do a lot of solves. It will improve your recognition time and familiarity with the cube and different cases in your method, which is probably the biggest contributor to your solves at those times, especially if you already have a cube like a Zhanchi. This is because there are two factors that affect how long it takes you to solve the cube: 1. Execution time (how long it takes you to perform the turns/algs and stuff) and 2. Inspection/recognition time (How long it takes you to figure out what you need to be doing or recalling what alg to use).
The second is likely a large part of your times where you sit with the cube looking for pieces (rotating/twisting the cube) and the delay between seeing the piece(s) and executing the algorithm.

[Kirjava]

Also, I've been told MANY times by some fairly upset youtubers that I should NOT be using a Zhanchi at my skill level. They're telling me it'll make me worse in the long run and that I should force myself to use a crap cube until that point. Is there any truth in that?

This is the worst myth in speedcubing, perpetuated by people who do not know what they're talking about.

Use whatever cube you prefer.

[soldii3runit]

When I switched from A crappy cube to a zhanchi, my time dropped 10secs so it is a myth.

[costello]

I'd record the solving of the cube and have it playing behind me on an lcd display while I gave my introduction, but that's so I could focus on my speech.

[applemobile]

Start with a solved cube, scramble it whilst Saying your speach backwards for 30 seconds then start talking forwards as you solve it. People will think you have mastered time travel and probably give you money to show them your secrets. Get an A on your assignment an recieve free money. Win.

[Cubenovice]

Would the format allow you to just do a walk-trough solve?
This way you can solve slowly instead of trying to force yourself to go fast.

[Dominate]

Do the prepared solve, but when you solve it just pretend you're a little surprise and remark that you did it faster than you usually do. That way you've got your ass covered if someone approaches you afterwards and asks to scramble it for you.

A tip for the prepared solve: Design your own solve backwards, using your favorite/most comfortable LL, F2L, and a simple cross. Maybe even make the cross only three moves or something.